Thermal Oxide Silicon Wafers

Thermal oxide silicon wafers feature a high-quality layer of Silicon Dioxide (SiO₂) grown directly on the silicon substrate at high temperatures. This oxide layer provides superior electrical insulation, surface passivation, and precise thickness control compared to deposited oxides.

Get a Quote

Related Materials

What Are Thermal Oxide Wafers Used For?

The advancing miniaturization of silicon chips increases the demand for high-performance silicon wafers. Thermal oxide layers are formed by heating silicon wafers to extreme temperatures (typically >1,000°C) in the presence of oxygen or water vapor. This process forces oxygen to diffuse into the silicon crystal, reacting to form a pure Silicon Dioxide (SiO₂) layer.

Key Applications

  1. Dielectric Layer in MOSFETs: The oxide layer serves as the gate dielectric in transistors, insulating the gate from the channel.
  2. Masking for Doping: SiO₂ blocks ion implantation and diffusion dopants (like Boron or Phosphorus), allowing precise patterning of active regions.
  3. Surface Passivation: The oxide ties up "dangling bonds" on the silicon surface, reducing electron-hole recombination and improving device efficiency.
  4. MEMS Fabrication: In Micro-Electro-Mechanical Systems, the oxide layer acts as a sacrificial layer or structural insulator.
  5. LOCOS Isolation: "Local Oxidation of Silicon" creates insulating regions between transistors to prevent electrical cross-talk.

Dry vs. Wet Oxidation

Dry Oxidation uses pure oxygen gas. It is slower but produces a denser, higher-quality oxide, ideal for thin gate oxides.

Wet Oxidation uses water vapor. It is much faster and is used for growing thick field oxides where speed is more critical than density.

Specifications

We supply thermal oxide wafers with oxide thicknesses ranging from 100Å (10nm) to 20,000Å (2µm). The underlying silicon wafers are typically Prime Grade to ensure the highest interface quality.